We Keep Coding

JTextArea - selection behavior on double / triple click + moving mouse

The problem: when you double click on word in JTextArea it is marked, but when you don't release the mouse button and try to mark next word, it is not marking whole word, but single characters instead.
It should mark the whole words (not single characters) when moving mouse (on double click). That's literally the default behavior in all programs which I tried, like: Notepad, Firefox, Chrome, Word, even Netbeans, etc.
Same thing with triple click (when holding and moving the mouse should mark the next line, not characters).
Any ideas? I had hard time Googling this, but since it's a very common thing I believe there must be a simple option or at least someone already have a solution.
Sample code:
public class TestJTextArea
{
public static void main(final String[] args)
{
final JPanel panel = new JPanel(new BorderLayout());
panel.setPreferredSize(new Dimension(500, 500));
panel.add(new JTextArea(), BorderLayout.CENTER);
final JFrame frame = new JFrame("Test");
frame.getContentPane().add(panel, BorderLayout.CENTER);
frame.pack();
frame.setResizable(false);
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
}

Maybe you need to create a customized Caret, for example:
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.text.*;
public class TestJTextArea2 {
public Component makeUI() {
String text = "The quick brown fox jumps over the lazy dog.";
JTextArea textArea1 = new JTextArea("default\n" + text);
JTextArea textArea2 = new JTextArea("setCaret\n" + text) {
#Override public void updateUI() {
setCaret(null);
super.updateUI();
Caret oldCaret = getCaret();
int blinkRate = oldCaret.getBlinkRate();
Caret caret = new SelectWordCaret();
caret.setBlinkRate(blinkRate);
setCaret(caret);
}
};
JPanel p = new JPanel(new GridLayout(2, 1));
p.add(new JScrollPane(textArea1));
p.add(new JScrollPane(textArea2));
return p;
}
public static void main(String[] args) {
EventQueue.invokeLater(() -> {
JFrame f = new JFrame();
f.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
f.getContentPane().add(new TestJTextArea2().makeUI());
f.setSize(320, 240);
f.setLocationRelativeTo(null);
f.setVisible(true);
});
}
}
class SelectWordCaret extends DefaultCaret {
private boolean wordSelectingMode = false;
private int p0; // = Math.min(getDot(), getMark());
private int p1; // = Math.max(getDot(), getMark());
#Override public void mousePressed(MouseEvent e) {
super.mousePressed(e);
int nclicks = e.getClickCount();
if (SwingUtilities.isLeftMouseButton(e) && !e.isConsumed() && nclicks == 2) {
p0 = Math.min(getDot(), getMark());
p1 = Math.max(getDot(), getMark());
wordSelectingMode = true;
} else {
wordSelectingMode = false;
}
}
#Override public void mouseDragged(MouseEvent e) {
if (wordSelectingMode && !e.isConsumed() && SwingUtilities.isLeftMouseButton(e)) {
continuouslySelectWords(e);
} else {
super.mouseDragged(e);
}
}
private void continuouslySelectWords(MouseEvent e) {
Position.Bias[] biasRet = new Position.Bias[1];
JTextComponent c = getComponent();
int pos = c.getUI().viewToModel2D(c, e.getPoint(), biasRet);
if(biasRet[0] == null) {
biasRet[0] = Position.Bias.Forward;
}
try {
if (p0 <= pos && pos <= p1) {
setDot(p0);
moveDot(p1, biasRet[0]);
} else if (p1 < pos) {
setDot(p0);
moveDot(Utilities.getWordEnd(c, pos - 1), biasRet[0]);
} else if (p0 > pos) {
setDot(p1);
moveDot(Utilities.getWordStart(c, pos), biasRet[0]);
}
} catch (BadLocationException bl) {
UIManager.getLookAndFeel().provideErrorFeedback(c);
}
}
}

Can you make a JToolBar undetachable?

I would like to make my JToolBar impossible to detach from its container but still let the user drag it to one of the container's sides.
I know about
public void setFloatable( boolean b )
but this won't allow the user to move the JToolBar at all.
Is there any way of doing this without overwriting ToolBarUI?
Also, is there an option to highlight its new position before dropping it?

It's not the most elegant solution, but it works.
public class Example extends JFrame {
BasicToolBarUI ui;
Example() {
JToolBar tb = new JToolBar();
tb.add(new JButton("AAAAA"));
tb.setBackground(Color.GREEN);
ui = (BasicToolBarUI) tb.getUI();
getContentPane().addContainerListener(new Listener());
getContentPane().add(tb, BorderLayout.PAGE_START);
setDefaultCloseOperation(EXIT_ON_CLOSE);
setSize(300, 300);
setLocationRelativeTo(null);
setVisible(true);
}
class Listener implements ContainerListener {
#Override
public void componentAdded(ContainerEvent e) {}
#Override
public void componentRemoved(ContainerEvent e) {
if (ui.isFloating()) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
ui.setFloating(false, null);
}
});
}
}
}
public static void main(String[] args) {
new Example();
}
}
Explanation:
Whenever the toolbar is moving to a floating state, it is instructed not do so. The only problem is that you have to wait for the EDT to finish the process for creating the floating window, and only then can you tell it not to float. The result is that you actually see the window created and then hidden.
Note:
I think that overriding the UI for the toolbar is a better solution, though it's possible that with a more intricate approach doing something similar to what I did will also work well.

works for me quite correctly on WinOS, old code from SunForum
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class CaptiveToolBar {
private Robot robot;
private JDialog dialog;
private JFrame frame;
public static void main(String[] args) {
//JFrame.setDefaultLookAndFeelDecorated(true);
//JDialog.setDefaultLookAndFeelDecorated(true);
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
new CaptiveToolBar().makeUI();
}
});
}
public void makeUI() {
try {
robot = new Robot();
} catch (AWTException ex) {
ex.printStackTrace();
}
final JToolBar toolBar = new JToolBar();
for (int i = 0; i < 3; i++) {
toolBar.add(new JButton("" + i));
}
frame = new JFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(400, 400);
frame.setLocationRelativeTo(null);
frame.add(toolBar, BorderLayout.NORTH);
final ComponentListener dialogListener = new ComponentAdapter() {
#Override
public void componentMoved(ComponentEvent e) {
dialog = (JDialog) e.getSource();
setLocations(false);
}
};
toolBar.addHierarchyListener(new HierarchyListener() {
#Override
public void hierarchyChanged(HierarchyEvent e) {
Window window = SwingUtilities.getWindowAncestor(toolBar);
if (window instanceof JDialog) {
boolean listenerAdded = false;
for (ComponentListener listener : window.getComponentListeners()) {
if (listener == dialogListener) {
listenerAdded = true;
break;
}
}
if (!listenerAdded) {
window.addComponentListener(dialogListener);
}
}
}
});
frame.addComponentListener(new ComponentAdapter() {
#Override
public void componentMoved(ComponentEvent e) {
if (dialog != null && dialog.isShowing()) {
setLocations(true);
}
}
});
frame.setVisible(true);
}
private void setLocations(boolean moveDialog) {
int dialogX = dialog.getX();
int dialogY = dialog.getY();
int dialogW = dialog.getWidth();
int dialogH = dialog.getHeight();
int frameX = frame.getX();
int frameY = frame.getY();
int frameW = frame.getWidth();
int frameH = frame.getHeight();
boolean needToMove = false;
if (dialogX < frameX) {
dialogX = frameX;
needToMove = true;
}
if (dialogY < frameY) {
dialogY = frameY;
needToMove = true;
}
if (dialogX + dialogW > frameX + frameW) {
dialogX = frameX + frameW - dialogW;
needToMove = true;
}
if (dialogY + dialogH > frameY + frameH) {
dialogY = frameY + frameH - dialogH;
needToMove = true;
}
if (needToMove) {
if (!moveDialog && robot != null) {
robot.mouseRelease(InputEvent.BUTTON1_MASK);
}
dialog.setLocation(dialogX, dialogY);
}
}
}

How to get Keybord input to console using `Robot` class?

I am trying to implement virtual keyboard using swing. I have made my own design , now If I press on button A it should print A on console. How to do this.? As of now I have done this much...
private void jButton8ActionPerformed(java.awt.event.ActionEvent evt) {
//System.out.println(" "+evt.getSource());
if(evt.getSource()==jButton8)
{
try{
Robot robot = new Robot();
robot.keyPress(KeyEvent.VK_A);
}
catch(Exception E){}
}
}
Can any one help me in this, and I am doing this in NetBeans IDE.

Although your question is not completely clear to me, the following code might be helpful:
public class VirtualKeyboardRobot {
private Robot robot;
public static void main(final String[] args) {
try {
new VirtualKeyboardRobot().test();
} catch (final AWTException e) {
e.printStackTrace();
}
}
private void test() throws AWTException {
final JFrame frame = new JFrame("Keyboard input to console using robot");
frame.setAlwaysOnTop(true);
frame.setFocusable(false);
frame.setBounds(100, 100, 800, 200);
frame.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
robot = new Robot();
robot.setAutoDelay(100);
final ActionListener buttonListener = actionEvent -> {
// See KeyEvent.VK_A: VK_A through VK_Z are the same as ASCII 'A' through 'Z' (0x41 - 0x5A).
final Object source = actionEvent.getSource();
if (source instanceof AbstractButton) {
// Switch from the virtual keyboard to the previous window.
typeKey(KeyEvent.VK_TAB, KeyEvent.ALT_MASK);
// Type the key.
typeKey((int) ((AbstractButton) source).getText().toUpperCase().charAt(0));
}
};
final JPanel keyboardPanel = new JPanel(new FlowLayout(FlowLayout.LEFT));
for (char key = 'a'; key <= 'z'; key++) {
final JButton button = new JButton(Character.toString(key));
button.setFocusable(false);
keyboardPanel.add(button);
button.addActionListener(buttonListener);
}
frame.getContentPane().setLayout(new BorderLayout());
frame.getContentPane().add(keyboardPanel, BorderLayout.NORTH);
final JTextArea textArea = new JTextArea(6, 28);
textArea.setFocusable(false);
frame.getContentPane().add(textArea, BorderLayout.CENTER);
frame.setVisible(true);
}
private void typeKey(final int keyCode, final int mask) {
if ((mask & KeyEvent.ALT_MASK) != 0)
robot.keyPress(KeyEvent.VK_ALT);
typeKey(keyCode);
if ((mask & KeyEvent.ALT_MASK) != 0)
robot.keyRelease(KeyEvent.VK_ALT);
}
private void typeKey(final int keyCode) {
robot.keyPress(keyCode);
robot.keyRelease(keyCode);
}
}

swings trouble with splash screen

I am trying to implement splash screen followed my main activity. Code below is what I have manged to do so far. And I am not able to get my splash screen working. Please help.
On running the the file its showing SplashScreen.getSplashScreen() returned null.What to do ?
SplashDemo.java
public class SplashDemo extends Frame implements ActionListener {
static void renderSplashFrame(Graphics2D g, int frame) {
final String[] comps = {"foo", "bar", "baz"};
g.setComposite(AlphaComposite.Clear);
g.fillRect(120,140,200,40);
g.setPaintMode();
g.setColor(Color.BLACK);
g.drawString("Loading "+comps[(frame/5)%3]+"...", 120, 150);
}
public SplashDemo() {
super("SplashScreen demo");
setSize(300, 200);
setLayout(new BorderLayout());
Menu m1 = new Menu("File");
MenuItem mi1 = new MenuItem("Exit");
m1.add(mi1);
mi1.addActionListener(this);
this.addWindowListener(closeWindow);
MenuBar mb = new MenuBar();
setMenuBar(mb);
mb.add(m1);
final SplashScreen splash = SplashScreen.getSplashScreen();
if (splash == null) {
System.out.println("SplashScreen.getSplashScreen() returned null");
return;
}
Graphics2D g = splash.createGraphics();
if (g == null) {
System.out.println("g is null");
return;
}
for(int i=0; i<100; i++) {
renderSplashFrame(g, i);
splash.update();
try {
Thread.sleep(90);
}
catch(InterruptedException e) {
}
}
splash.close();
setVisible(true);
toFront();
}
public void actionPerformed(ActionEvent ae) {
System.exit(0);
}
private static WindowListener closeWindow = new WindowAdapter(){
public void windowClosing(WindowEvent e){
e.getWindow().dispose();
}
};
public static void main (String args[]) {
SplashDemo test = new SplashDemo();
}
}

Create your splash screen image, say MySplashyScreen.gif, and put it in a directory called images (or wherever you like).
Then on startup use this command line:
java -splash:images/MySplashyScreen.gif SplashDemo

How to change font size of JButton according to its size?

I have a java application - a calculator. I want to resize font of buttons dynamically with resizing the window of the app. How to implement it?
My idea is using ComponentEvents. I have initial size of the window of application and initial fonts' sizes. I want to change font size according to button's size, affected by window size change. The problem is how to use the ratio [initial window size] / [initial font size] in the overriden method? The ratio is different for each font.
import javax.swing.*;
import java.awt.*;
import java.awt.event.ComponentEvent;
import java.awt.event.ComponentListener;
public class Main extends JFrame {
public Main() {
super("Test");
JPanel cPane = (JPanel) getContentPane();
cPane.setLayout(new BorderLayout());
MyButton sampleButton = new MyButton("Sample text");
sampleButton.setFont(new Font("Sans Serif", Font.PLAIN, 20));
MyButton a, b, c, d;
a = new MyButton("a");
b = new MyButton("b");
c = new MyButton("c");
d = new MyButton("d");
cPane.add(a, BorderLayout.PAGE_START);
cPane.add(b, BorderLayout.PAGE_END);
cPane.add(c, BorderLayout.LINE_START);
cPane.add(d, BorderLayout.LINE_END);
cPane.add(sampleButton, BorderLayout.CENTER);
setSize(300, 200);
setResizable(true);
setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
setVisible(true);
}
public static void main(String... args) {
new Main();
}
class MyButton extends JButton implements ComponentListener {
public MyButton(String title) {
super(title);
}
#Override
public void componentResized(ComponentEvent e) {
//resizing font
}
#Override
public void componentMoved(ComponentEvent e) {
}
#Override
public void componentShown(ComponentEvent e) {
}
#Override
public void componentHidden(ComponentEvent e) {
}
}
}

See how you go with this code using GlyphVector to determine the largest Font that will fit.
The GUI was a little shaky unless there was a delay between setting the frame visible and adding the ComponentListener. I solved that by delaying adding the listener using a single shot Swing Timer.
Is is based on Calculet which is a fully functioning (if simple) calculator using the ScriptEngine.
import java.awt.*;
import java.awt.event.*;
import java.awt.font.*;
import java.awt.geom.Rectangle2D;
import java.awt.image.BufferedImage;
import javax.swing.*;
import javax.swing.border.EmptyBorder;
import java.util.ArrayList;
import javax.script.*;
import javax.swing.border.Border;
class SwingCalculator implements ActionListener, KeyListener {
JTextField io;
ScriptEngine engine;
ArrayList<JButton> controls;
final BufferedImage textImage = new BufferedImage(
100, 100,
BufferedImage.TYPE_INT_ARGB);
public int getMaxFontSizeForControls() {
Graphics2D g = textImage.createGraphics();
FontRenderContext frc = g.getFontRenderContext();
int maxSize = 500;
for (JButton b : controls) {
// skip the = button..
if (!b.getText().equals("=")) {
int max = getMaxFontSizeForControl(b, frc);
if (maxSize > max) {
maxSize = max;
}
}
}
g.dispose();
return maxSize;
}
public int getMaxFontSizeForControl(JButton button, FontRenderContext frc) {
Rectangle r = button.getBounds();
Insets m = button.getMargin();
Insets i = button.getBorder().getBorderInsets(button);
Rectangle viewableArea = new Rectangle(
r.width -
(m.right + m.left + i.left + i.right),
r.height -
(m.top + m.bottom + i.top + i.bottom)
);
Font font = button.getFont();
int size = 1;
boolean tooBig = false;
while (!tooBig) {
Font f = font.deriveFont((float) size);
GlyphVector gv = f.createGlyphVector(frc, button.getText());
Rectangle2D box = gv.getVisualBounds();
if (box.getHeight() > viewableArea.getHeight()
|| box.getWidth() > viewableArea.getWidth()) {
tooBig = true;
size--;
}
size++;
}
return size;
}
SwingCalculator() {
// obtain a reference to the JS engine
engine = new ScriptEngineManager().getEngineByExtension("js");
JPanel gui = new JPanel(new BorderLayout(2, 2));
controls = new ArrayList<JButton>();
JPanel text = new JPanel(new GridLayout(0, 1, 3, 3));
gui.add(text, BorderLayout.NORTH);
io = new JTextField(15);
Font font = io.getFont();
font = font.deriveFont(font.getSize() * 1.7f);
io.setFont(font);
io.setHorizontalAlignment(SwingConstants.TRAILING);
io.setFocusable(false);
text.add(io);
JPanel buttons = new JPanel(new GridLayout(4, 4, 2, 2));
gui.add(buttons, BorderLayout.CENTER);
addButton(buttons, "7");
addButton(buttons, "8");
addButton(buttons, "9");
addButton(buttons, "/");
addButton(buttons, "4");
addButton(buttons, "5");
addButton(buttons, "6");
addButton(buttons, "*");
addButton(buttons, "1");
addButton(buttons, "2");
addButton(buttons, "3");
addButton(buttons, "-");
addButton(buttons, "0");
addButton(buttons, ".");
addButton(buttons, "C");
addButton(buttons, "+");
JButton equals = new JButton("=");
equals.addKeyListener(this);
controls.add(equals);
equals.addActionListener(this);
gui.add(equals, BorderLayout.EAST);
gui.setBorder(new EmptyBorder(5, 5, 5, 5));
final JFrame f = new JFrame("Calculet");
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.setContentPane(gui);
f.pack();
f.setMinimumSize(f.getSize());
f.setLocationByPlatform(true);
f.setVisible(true);
final ComponentListener cl = new ComponentAdapter() {
#Override
public void componentResized(ComponentEvent e) {
int ii = getMaxFontSizeForControls();
for (JButton b : controls) {
if (!b.getText().equals("=")) {
b.setFont(b.getFont().deriveFont((float) ii));
}
}
}
};
ActionListener al = new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
f.addComponentListener(cl);
}
};
Timer t = new Timer(500, al);
t.setRepeats(false);
t.start();
}
public void addButton(Container c, String text) {
JButton b = new JButton(text);
b.addActionListener(this);
b.addKeyListener(this);
controls.add(b);
c.add(b);
}
public void calculateResult() {
try {
Object result = engine.eval(io.getText());
if (result == null) {
io.setText("Output was 'null'");
} else {
io.setText(result.toString());
}
} catch (ScriptException se) {
io.setText(se.getMessage());
}
}
public void actionPerformed(ActionEvent ae) {
String command = ae.getActionCommand();
if (command.equals("C")) {
io.setText("");
} else if (command.equals("=")) {
calculateResult();
} else {
io.setText(io.getText() + command);
}
}
private JButton getButton(String text) {
for (JButton button : controls) {
String s = button.getText();
if (text.endsWith(s)
|| (s.equals("=")
&& (text.equals("Equals") || text.equals("Enter")))) {
return button;
}
}
return null;
}
/*
* START - Because I hate mice.
*/
public void keyPressed(KeyEvent ke) {
}
public void keyReleased(KeyEvent ke) {
String s = ke.getKeyText(ke.getKeyCode());
JButton b = getButton(s);
if (b != null) {
b.requestFocusInWindow();
b.doClick();
}
}
public void keyTyped(KeyEvent ke) {
}
public static void main(String[] args) {
Runnable r = new Runnable() {
#Override
public void run() {
new SwingCalculator();
}
};
// Swing GUIs should be created and updated on the EDT
// http://docs.oracle.com/javase/tutorial/uiswing/concurrency
SwingUtilities.invokeLater(r);
}
}

Compare the approaches shown here and here. The former uses an available JComponent.sizeVariant.
The latter cites an example using FontMentrics.
Or TextLayout.